Clinical pharmacology and therapeutics
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Clin. Pharmacol. Ther. · Oct 2004
Randomized Controlled Trial Clinical TrialAngiotensin-converting enzyme inhibition and smoking potentiate the kinin response to cardiopulmonary bypass.
This study tested the hypothesis that angiotensin-converting enzyme (ACE) inhibitors potentiate activation of the kallikrein-kinin system during cardiopulmonary bypass (CPB). ⋯ Preoperative ACE inhibitors and smoking potentiate the kinin response to CPB and may contribute to the hemodynamic and fibrinolytic response observed during CPB.
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Clin. Pharmacol. Ther. · Oct 2004
Clinical Trial Controlled Clinical TrialEffect of St John's wort on imatinib mesylate pharmacokinetics.
Imatinib is a potent inhibitor of the Bcr-Abl and c- kit tyrosine kinases and is approved for the treatment of Philadelphia chromosome-positive chronic myelogenous leukemia and gastrointestinal stromal tumors. Because imatinib is predominantly metabolized by cytochrome P450 (CYP) 3A4, its pharmacokinetics may be altered when it is coadministered with drugs or herbs (eg, St John's wort) that modulate CYP3A4 activity. Thus we examined the effects of St John's wort on imatinib pharmacokinetics. ⋯ These data indicate that St John's wort increases imatinib clearance. Thus patients taking imatinib should avoid taking St John's wort. Concomitant use of enzyme inducers, including St John's wort, may necessitate an increase in the imatinib dose to maintain clinical effectiveness.
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Clin. Pharmacol. Ther. · Oct 2004
Randomized Controlled Trial Clinical TrialDifferent dosage regimens of rabeprazole for nocturnal gastric acid inhibition in relation to cytochrome P450 2C19 genotype status.
For the treatment of gastroesophageal reflux disease, intragastric pH should be lower than 4.0 for no more than 4 hours a day (<16.7%). We aimed to develop optimal dosage regimens for rabeprazole to control nocturnal acidity in relation to cytochrome P450 (CYP) 2C19 genotypes. ⋯ We propose that rabeprazole dosage regimens for sufficient acid inhibition are 20 mg once daily for PMs, 20 mg twice daily for heterozygous EMs, and 10 mg 4 times daily for homozygous EMs or heterozygous EMs.
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Clin. Pharmacol. Ther. · Oct 2004
Clinical TrialQT interval prolongation after oxytocin bolus during surgical induced abortion.
Although oxytocin, a uterotonic agent, may cause short-term vasodilation that results in severe hypotension, it is still routinely given as an intravenous bolus injection during surgical suction curettage. Two reported cases of ventricular tachycardia after oxytocin bolus in patients with long QT interval syndrome led us to assess the effect of oxytocin on QT interval. ⋯ Oxytocin intravenous bolus induced a large and transient QTc interval prolongation, suggesting that it may lead to proarrhythmia in circumstances favoring QTc interval increase.